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W, A. .sowas y FAN Filed May 25,' 1932 4 Sheets-Sheet l INVENTOR W. A.JONES May 8, l934.

FAN

Filed May 23, 1932 4 sheets-sheet 2 INVENTOR W. A. JQNES FAN Filed May25. l932 4 Sheets-Sheet 3 Wj. FAN

Filed; May 23, 1952 i Sheets-Sheet 4 Patented May 8, 1934 UNITED STATESFAN William Anthony Jones,

West New Brighton, N. Y.

Application May 23, 1932, Serial No. 612,952

15 Claims.

My invention relates particularly to fans which receive gas at one sideand discharge it at the other side and is a modification of thatdescribedin United States Patent #1,447,554 issued to me March 6, 1923.

This modification consists in making the angularity of the stationaryblades and of the moving blades each diierent for different distancesfrom the center of the shaft so that for a definite volume of gas andspeed of fan, the resulting velocity of the gas will be the same for alldistances from the center of the shaft, with resulting reduction ineddies and in friction loss.

This result may be obtained without much thrust on the vfan wheelbearings by making the wheel blades with a retreating angle at theirouter radius and an advancing angle at their inner radius, so that theresulting axial thrusts on the anwheel about neutralize each other.Nearly 20 all of the thrust is on the stationary blades.

Having in mind that the energy of motion and the pressure against whichthe motion will drive a gas is asthe square of the velocity, thedesirability of having the samevelocity atvall radii is evident. If thevelocity were directly as the radii so that the velocity at the outerradius was, for instance, six units while the velocity at the innerradius was ve units, then the squares of these quantities would be asthirty-six is to twenty-five, which would be the relation of thepressure at the outer radius compared to that at the inner radius.

Referring to the accompanying drawings; Fig. l is a longitudinal sectionof a two-stage fan with stationary blades and with chords of curvedmoving blades each having dilerent angularities which compensate for thedilerent speeds of the inner and the ou'ter radii of the fan wheel.

Fig. 2 is a part end view of the fan shown in o Fig. l.

Fig. 3 is a part development of the side View of this fan, showing shapeof blades and openings for discharge of dust accompanied by some gas.

Fig. 4 and Fig. 5 are enlarged views of moving blades showing differencein angularity of chords at inner and `at outer radii.

Fig. 6 is a longitudinal section of an eight-stage fan with surfaces ofmoving blades formed of straight lines corresponding to the chords ofthe moving blades shown in Fig. 1 and otherwise identical with Fig. 1.

` Fig. 7 isa part development showing a side View of the blades when thecasing is removed to indicate the shape of th; blades, for'the fan shownin Fig. 6, being similar to Fig. 3 which is such a development for thefan shown in Fig. 1.

Fig. 8 is an enlarged view of stationary and moving blades ofeight-stage fan, showing difference in angularity of lines at insideradius and at outside radius, similar to Fig. 4.

v Fig. 9 is an enlarged part sectional view through the forward and rearedges of the fan wheel and stationary cones showing the edges beveled.

Fig. 10 is a diagram showing lines representing velocities of gas in itspassage through the fan.

Figure 11 is a diagram showing lines representing velocities of gas inits passage through a fan, with a single row of moving blades, the fanbeing otherwise like that shown in Figs. 6, 7 and 8, with blades formedof straight lines.

Figure 12 is a diagram-showing the manner of applying the method ofdevelopment disclosed in Fig. l1, to the multiple stage fan shown inFigs. 6, 7 and 8.

Similar parts are referred to by similar numerals throughout the severalviews.

Referring to the drawings:

A fa wheel, 1; provided with blades, 2, is mounted on a shaft, 3;'Shaft, 3, is driven from shaft, 4, through gears, 5, and 6.

The fan casing is represented as having an inlet part, 7,-an outletpart, 8, and a central part, 9, the latter made of pieces joined byflanges, 10, so that the parts can-be conveniently removed.

A conical shield, 11, concentric with the inlet part, 7, shields thecentral part of the fan wheel, 1. A similar shield, 12, shields thecentral part of the wheel in the outlet part. 8.

The space, 13, between the conical shield, 11, and the inlet part, 7, ofthe casing, forms a passage of gradually decreasing area for gas as itapproaches the fan wheel blades, 2. Stationary guide `vanes, 14, in thespace, 13, between the conical shield, 11, andthe casing, 7, determinethe direction of flow of gas to the wheel, 1.

These guide blades, 14, are more obliqueto the axis near the wheel, atthe outside radius at, l5, than at the inside radius, at 16. 'Similarstationary guide vanes, 17, in the space, 18, between the conicalshield, 12, and the casing, 9, determine the direction of ow of gas asit leaves the blades of the wheel. These guide blades are also moreoblique to the axis nearthe wheel at the outside radius, at 19, than atthe inside radius, at 20.

Inclination of the stationary Varies, 14, and, 17. with respect to theaxis causes an axial thrust ou the gas Without a corresponding axialthrust oi: the fan wheel.

that the wheel in effect overlaps the cones, tending to add to thepressure on the inlet side of the wheel and to decrease the pressure onthe outlet side of the wheel. Wheel disks are provided with openings,23, all to avoid difference in pressure on the two sides of the wheel.'I f Beyond the Wheel a cylindrical baffle plate, 24, is joined to theshell, 8, at, 25, and presents an opening at 26 for ow of dust-laden gasto openings 27 which discharge into a girth channel, 28, terminating inan outlet, 29. i

Referring to the diagram, Fig. 10, line 30-31 being proportional to theinner radius, line 30-3'7 being proportional to the outer radius, thenline 30-32, and line 30--38 represent the direction and velocity of flowof gas approaching the fan as determined by the inclinations of thestationary blade at the inside radius and at the outside r'adius, and atan assumed volume equal to five-y eighths of thefree-ilow volume of gas.

Lines 3l-32, and lines 3'7--38 represent velocities, relative tothefan`wheel, at the inside and at the outside, of gas. as it approachesthe wheel.

Lines 32-33, and 38--39 represent velocities of gas, relativeto the fanwheel, as it leaves the wheel.

the velocities at the inside and at the outside which would obtain butfor friction and but for the outlet pressure being greater than theinlet pressure.

The squares ofthe lengths of these lines cornpared to the squares of thelengths of .lines 13D-32,.-

and 30-38 is proportional to the increase in pressure and frictionloss.,

The stationary vanes, 14, at the inlet side of the fan and, 1'?, at theoutlet side of the "fan, determine the direction of gas flow as itapproaches and as it leaves the fan.

Vanes, 17, are subject to a slight impact of gas,

due to angles somewhat less than those between lines connecting points35-324-36, 'and points 41-38-42. Other blades are without impact underthe assumed conditions, except at their edges.

' Absence of impactconduces to efiiciency.

vThe constructionshown gives a relatively long axial travel for dust andgas and a relativelyv long time for the separation of the extremelysmall flocculent ash resulting from burning powdered coal. This isparticularly thefcase for the mult'iplef-stage fanwhich also results ingreater pressure for a givenspeed.

Y As is known, the elastic air particles bounce from a'surface againstwhich they impinge at an angle equal to that with whichthey strike thesurfaceybvhereas particles of inelastic water slide from the surface anddo not bounce from the surface. Accordingly, it will be readilyunderstood that whereas for.` a propeller to act inwater the Y pitchshould be constant for all radii, this is not the case for a propellerto act in air. s

For theV apparatus described in this invention, making the sinevof theangle between the stationary vanes and the axis directly proportional tothe radius as shown, results in equal entering velocity at all radii,for a given percentage of the free flow volume, as diagram, Fig. 10,shows. The pitch increases towards the center.

In Fig. 11, I have shown how the inner and the outer lines of thestationary vanes and of the moving vanes of the fan are determined togive line 32-l34, representing gas velocity at the inner edge equal toline 38--140, representing gas velocity at the outer edge of the blade.Curved blades, 186, without batting or bouncing action, could be usedinstead of straight blades 2.

Figure 12 shows in heavy straight lines the shape of the inner edge ofstationary and of moving blades using bouncing action and in lightdotted curved lines shows the possible shape of the inner edges of theblades without bouncing action but arranged so that the gas slides ontoand off of the blades with'out impact.

With the above in mind it is easy to understand why ordinary fanssometimeshave an efficiencyl results iny about the same change invelocity and direction of ow with straight fan blades, like one of thoseshown in`Figs. 6, '7 and8, as for the curved blade, asshown in Figs. 1,2 and 3, where/impact is avoided for a given percentage of free iiowvolume. The curved blade also avoids interfering withthe ow fromadjacent blades.

A spray of water or nonvolatile liquid, 50, discharged into theincominggas from pipe, 51, may

be used to give weight to extremely light dust and assist its'separation. The spray of water may also be used periodically to wash theinside surfaces of the apparatus.

,Oil pipes, 52, 53, 54 and 55, convey oil for lubricating and coolingthe bearings.

I claim: 1. Inapparatus for causing gas to ow from a lower pressure to ahigher pressure, the combination' of a fan Wheel with blades, a casinghaving a concentric conical shield at the inlet side of the fan wheel, asecond conical shield at the outlet sideof the fan Wheel, stationaryvanes between the` conical shields and the casing, the stationary vanesnear the wheel being more oblique to the axis at their outer radius thanat their inner radius, so that the sine of the angle of inclinationmeasured on a plane perpendicular to the radius is directly proportionalto the radius. 2. In apparatus for causing gas to flow from a lowerpressure to a higher pressure, the combination of a fan wheel withblades, a casing having a concentric conical shield at the inlet side ofthe fan wheel, a second conical shield at the outlet side of the fanwheel, oblique stationary vanes between the conical shields and thecasing, the stationary vanes near the wheel being more oblique to theaxis(at their outer radius than at their inner radius, so that the sineof the angle of the inclination is directly proportional to the radius,

the blades of the wheel being made so that lines i 3. In apparatus forcausing gas to flow from a"A lower pressure to a higher pressure, thecombination of a fan wheel with blades, a casing having a concentricconical shield at the inlet side of the fan wheel, a second conicalshield at the outlet side of the fan wheel, oblique stationary vanesbetween the conical shields andthe casing, the

stationary vanes near the wheel being more oblique to the axis at theirouterradius than at their inner radius, so that the sine of the angle ofthe inclination is directly proportional to the radius, the blades ofthewheel being made so that lines connecting their forward and rear edgesare at different angles measured on a plane perpendicular to the radiusfor the inner radius and the outer radius.

4. In apparatus for causing gas to ow from a lower pressure to a higherpressure, the combination of a fan wheel with blades, a casing having aconcentric conical shield at the inlet side of the fan wheel, a secondconical shield at the outlet side of the fan wheel, stationary vanesbetween the conical shields and the casing, the stationary vanes nearthe wheel being more oblique to the axis at their outer radius than attheir inner radius, so that the sine of the angle of the inclination isdirectly proportional to the radius, the blades of the wheel being madeso that lines connecting their forward and rear edges are at differentangles referred to a transverse plane for the inner radius and the outerradius, and the blades of the wheel are made curved so that for a givenspeed of fan and volume of gas the curve of the blade will be tangent tothe path of the entering gas rrelative to the blade at the inside radiusand at the outside radius, as shown.

5. In apparatus for causing gas to flow from a lower pressure -to ahigher pressure, the combination of a fan wheel with blades, a casinghaving a concentric conical shield at the inlet sideof the fan wheel, asecond conical shield at the outlet side of the fan wheel, stationaryvanes between the conical shields and the casing, the stationary vanesnear the wheel being more oblique to the axis at their outer radiusthant at their inner radius, so that the sine of the angle of theinclination is directly proportional to the radius,

the blades of the wheel being made so that linesl connecting-'theirforward and rear edges are atv dierent angles referred to a transverse,plane for the inner radius and the outer radius, and the blades of thewheel are made curvedso that for a given speed of fan and volume of gasthe curve of the blade will be tangent to the path of the enteringgas-relative to the `blade at the inside radius and at-the outsideradius, and the action of the blade imparts about the same velocity tothe gas at the inner radius and at the outer radius.

. 6. In apparatus for causing gas to ow from a lower pressure'fto ahigher pressure, thev come,

bination of a fan wheel with more than one row of blades, a casinghaving a concentric conical shield at the inlet side of the fan wheel, asecond conical shield at the outlet side of the fan wheel. and obliquestationary blades between the conical shields and the casing and betweentherows of blades of the wheel, the stationary vanes being more obliqueto the axis at their outer radius than at their inner radius, sothatlthe sine ofthe Yangle of their inclination measured on a planeperpendicular to the,l radius is directly proportional to the radius.

7. In apparatus for causing gas to ow from a lower pressure to a higherpressure, the com-,7,

Ioblique stationary blades between the conical shields andthe casing andbetween the rows of blades of the wheel, the stationary vanes near thewheel being more oblique to the axis at their outerradius lthan at theirinner radius, so that the sine of the angle of the inclination is`directly, proportional to the radius, the blades of each. row of thewheel, being made so` that lines connecting their forward and rear edgesare at an advancing angle for the inner radius tothereby cause the gasto move circumferentially faster than theA wheel and at a retreatingangle for the outer radius.

8. I n apparatus for causing gas to owvfrom a lower pressure to a higherpressure, the combination of a fan wheel with more than one row ofblades, a casing having a concentric conical shield at the inlet side ofthe fan wheel, a second conical shield at the outlet'side of the fanwheel, and oblique stationary blades between the conical shields and thecasing and between the rows of blades ofthe wheel, the stationary vanesnear the Wheel being more oblique to the axis at their outer radius thanat their inner-radius, so that the sine of the angle of the inclinationis directly proportional to the radius, the blades of each row of thewheel, being made so that lines connecting their forward and rear edges;are at different angles measured on a plane perpendicular to the radiusfor the inner radius and the outer radius.

9. In apparatus forycausing gas to flow .from a lower pressure to ahigher pressure, the combination of a fan wheel withblades, a casinghaving `a,concentric conical shield at the inlet side of the fan wheel,a second conical shield at the outlet side of the fan wheel, stationaryvanes,

between the conical shields and the casing, the stationary vanes nearthe wheel being more oblique to the axis 'at their outer radius than attheir inner radius, so that the sine of the angle of inclinationmeasured on a plane perpendicular to the radius is directly proportionaltothe radius, an inlet for gas at one side of the fan wheel, an outletfor gas at the other side of the fan wheel, and a second outlet for`dust at a greater distance from the center than the first outlet.

10. In apparatus for causing gas to flow from a lower pressure toAahigher pressure, the combination of a fan wheel with blades, a. casinghaving a concentric conical shield. at the .inlet side of the fan wheel,a second conical shield ait the radius, the blades of the wheel beingmade so, that lines connecting their forward and rear' edges are at anadvancingangle so that the gas moves circumferentially faster thanthewheel for the inner radius and at a retreating angle for the outerradius, an inlet for gas at one side of the fan wheel, an outlet for gasat the ,other side of the fan wheel, a second outlet for dust at agreater distance from first outlet. t

11. In apparatus for causing gas to flow from aflower pressure to ahigher pressure, the combination of a fan wheel with blades, a casinghaving a concentric conical shield at the inlet side of the fan wheel, asecond conical shield at the outlet side of the fan wheel, 'and obliquestationary vanesbetween the conical shieldsand the casing, thestationary vanes near the Wheel being more oblique to the axis at theirouter radius than at their inner radius, so that the sine of the angleof the inclination is directly prothecenter than the portional to theradius, the blades of the wheel being made so that lines connectingtheir forward andrear edges are at diierent angles measured on a planeperpendicular to the radius for the inner radius and the outer radius,an inlet for gas at one side of the fan wheel, an outlet for gas at theother side of the fan wheel, a second outlet for dust at a Agreaterdistance from the center than the rst outlet. 4

- l2. In apparatus for causing gas to flow from a lower pressure to ahigher pressure, the combination of a fan wheel with more lthan one rowof blades, acasing having a concentric conical shield at the inlet sideof the fan Wheel, a second conical shield at the outlet side of the fanwheel, and oblique stationary vanes between the conicalshields and thecasing and between the rows of blades of the wheel, the stationary vanesnear the wheel being more oblique to the axis at their outer radiusthanat their inner radius, so that the sine of the angle of theinclination is directly proportional to the radius, the blades of thewheel being made so that lines connecting their forward and rear edgesare at different angles measured on a plane perpendicular to the radiusfor the inner radius and the outer radius, an inlet for gas vat one sideof the fan wheel, an outletior gas at the other side of the fan wheel, asecond outlet ,for dust at a greater distance from the center than thefirst outlet. i

13. In apparatus for causing,V gas to flow from a lower pressure to ahigher pressure, the combination of a fan wheel with more than one rowof blades, a casing having a concentric conical shield at the inlet sideof the fan wheel, a second conical shield at the outlet side of the fanwheel, and stationary vanes between the conical shields and the -casingand between the rows of blades of the wheel, the stationary vanes nearthe wheel being more oblique to the axis at their outer radius than attheir inner radius, so that the sine of the angle of the inclination isdirectly proportional to the radius, the blades of the wheel being madeso that lines connecting their forward and rear edges, for each row, areat different angles measured on a plane perpendicular to the radius fortheinner radius and the outer radius,

and the blades of the Wheel are curved so that for a given speed of'fanand volume of gas the curve of the'blade will be tangent to the path ofthe entering gas relative to that blade, at the inside radius and at theoutside radius.

14. In apparatus for causing gas to ow from a 'lower pressure to ahigher pressure, the cornbination of a fan wheel with more than one rowof blades, a casing having a concentric conical shield at the inlet sideof the fan wheel, a second conical shield at the outlet side ofthe fanwheel, stationary vanes between the conical shields and the casing andbetween the rows of blades of the wheel, the stationary vanes near thewheel being more oblique to the axis at their outer. radius l than attheir inner radius, so that the sine of the angle of the inclination isdirectly proportional to the radius, the blades of the wheel being madeso that lines connecting their forward and rear edges, for each row, areat different angles measured on a plane perpendicular to the radius forthe inner radius and the outer radius, and the blades of the wheel arecurved so that for a given speed of fan and volume of gas the curve oi'the blade will be tangent to the path of the entering gas relative tothe blade, at the inside "radiusand at the outside radius, an inletforgas at one side of the fan wheel, an outlet for gas at the other sideof the fan wheel, and a second outlet for dust at a greater distancefrom the center than the first outlet. g

V15. In apparatus for causing gas to flow from a lower pressure to ahigher pressure, the combination of a fan wheel with blades, a casinghaving a concentriciconical shield at the inlet side of the fan wheel, asecond conical shield at the outlet side of the fan wheel, andstationary vanes .between the conical shields and the casing, thestationary vanes near the wheel. being more oblique to the axis at theirouter radius than at. their inner radius, so that the sine of the angleof v WILLIAM ANTHONY JONES.

